請問各位先進要如何透過Delphi程式去列印目前螢幕上的畫面呢??

procedure TForm1.mmPrintClick(Sender: TObject);
var
I: Integer;
bmp: TBitMap;
OldPath: string;
begin
OldPath := GetCurrentDir;
try
bmp := GetFormImage;
PRINT_BITMAP(bmp);
finally
_free_(bmp);
end;
finally
SetCurrentDir(OldPath);
end;
end;
procedure TForm1.PRINT_BITMAP(bmp: TBitMap);
var
Info: PBitmapInfo;
InfoSize: DWORD;
Image: Pointer;
ImageSize: DWORD;
Bits: HBITMAP;
DIBWidth, DIBHeight: LongInt;
begin
// Printer.Orientation := poLandscape;//橫印
Printer.BeginDoc;
try
Printer.Title := 'Printer.Title';
Canvas.Lock;
try
{ Paint bitmap to the printer }
with Printer do
begin
Bits := bmp.Handle;
GetDIBSizes(Bits, InfoSize, ImageSize);
Info := AllocMem(InfoSize);
try
Image := AllocMem(ImageSize);
try
GetDIB(Bits, 0, Info^, Image^);
with Info^.bmiHeader do
begin
DIBWidth := biWidth;
DIBHeight := biHeight;
end;
StretchDIBits(Canvas.Handle, 0, 0, PageWidth, PageHeight, 0, 0,
DIBWidth, DIBHeight, Image, Info^, DIB_RGB_COLORS, SRCCOPY);
finally
FreeMem(Image, ImageSize);
end;
finally
FreeMem(Info, InfoSize);
end;
end;
finally
Canvas.Unlock;
end;
finally
Printer.EndDoc;
end;
end;

感謝Jow的回覆,謝謝